LANSING, Mich. (WLNS) — In the last week, most of the United States had to deal with some extremely cold temperatures.

Mid-Michigan experienced wind chills of nearly -20 degrees.

In Montana, wind chills ranged from -40 to even -70 degrees below zero.

It’s not a surprise to know that this outbreak of arctic air broke a few records.

A record overnight low of -42 degrees was recorded in Casper, Wyoming on Thursday.

The cold air made it one of the coldest Christmas’ in the Tampa Bay area in more than 30 years.

The reason for this cold air outbreak is the Polar Vortex.

The term has become quite popular on social media in the past decade, but what does it actually mean?

The Polar Vortex refers to a batch of extremely cold air that is over the poles.

Normally, this cold air is contained by the polar jet stream that consists of winds that are tens of thousands of feet above the ground, and going at 80-100 mph.

The strong winds usually keep the vortex and the cold air trapped around the poles.

As the winds begin to weaken, that cold air can’t be contained as well, so it begins to travel south.

That is what mid-Michigan dealt with this past week, but it looks like there is some good news in the regional forecast.

The cold air is not permanent, in fact, there is a nice warm-up coming our way.

Temperatures are likely to be in the upper 40s to nearly 50s to ring in the New Year.

Even though the term Polar Vortex has been popularized on social media over the past decade or so, it has always been part of the weather.

So the next time that you hear that phrase it just means it might be time to grab that heavier winter coat and prepare for a brief blast of really cold air.